Copper is of importance for the development of upcoming technologies. The majority of copper is extracted by smelting of copper concentrate obtained from copper ores after flotation. However, these concentrates may possess a mineralogical bonded content of As and other impurities, for example, Sb and Bi, which constitute penalty elements. The removal of these elements is necessary due to their negative influence on the copper refinery process. In addition, the cost-effective production of arsenic-poor copper concentrates for smelting is important. The purpose of this study was to develop a low-cost, tailor-made approach for alkaline sulfide leaching to produce an arsenic-poor copper concentrate. Whereby, kinetics of arsenic dissolution were studied to develop and establish the reaction mechanism and control mode. Leaching kinetic models for arsenic reduction from two different Chilean copper concentrates, which contain both Enargite-Tennantite (as main As-containing minerals), are presented in this study. At first, the key leaching parameters for arsenic removal by alkaline sulfide leaching, such as temperature, sodium sulfide and hydroxide concentrations, and solid-to-liquid ratio were optimized. Under the studied conditions, arsenic removal achieved at T = 80 °C, [NaOH] = 2.5 M, [Na2S*3H2O] = 2 M, and solid-to-liquid ratio = 1/10 g/mL was similar to that obtained during partial roasting. Then, kinetic models for arsenic removal were developed. It was discovered that during the early phases of leaching, the dissolution kinetics of As are controlled by both chemical reaction and diffusion at the product layer generated on the outer surface of Enargite or Tennantite. Later, As dissolution is completely controlled by diffusion at the product layer.